FACTBOX - Key names in alleged Eq. Guinea coup plot

(Reuters) - Mercenary Simon Mann went on trial in Equatorial Guinea on Tuesday accused of leading a failed coup against the oil-producing country in 2004.

Below are brief portraits of Mann and Mark Thatcher, son of former Prime Minister Margaret Thatcher. He was named as an organiser of the plot.

SIMON MANN

Simon Mann, 55, is an Eton-educated former army officer turned mercenary who has already served four years in a Zimbabwean jail after being found guilty of attempting to buy arms for the alleged plot.

Mann is a descendant of Britain's beerocracy, the group of brewers who accumulated vast wealth and influence in the mid-20th century. His father George captained the England cricket team in the 1940s as his father had before him in the 1920s.

Simon went an altogether different route.

A South African citizen with a home in the plush Cape Town neighbourhood of Constantia, Mann worked with former mercenary groups Executive Outcomes and later with Tim Spicer's Sandline International.

Mann was arrested at Harare airport in March 2004 with a plane load of weapons and men. He said they were heading to the Democratic Republic of Congo to provide diamond mine security.

But other alleged coup plotters were detained in Equatorial Guinea, casting doubt on the alibi, and Mann was tried and found guilty of violating Zimbabwean immigration, firearms and security laws and sentenced to seven years in jail.